Flexible coupling



H. C. MONROE FLEXIBLE COUPLING Filed April 5, 1946 MOTOR O2 GEAR REDUCED lNVENTOR 1962er' C. 09a/vece.

m. ATTORNEY Aug. 28, l95v1 WlTNESSES: f5, www

Patented Aug. 28, 1951 FLEXIBLE COUPLING v Harry C. Monroe, Baltimore, ll/Id., assigner to Koppers Company, Inc., Pittsburgh, Pa., a corporation of Delaware Application April 3, 1946,1Seria1 No. 659,354

4 Claims.

. 1 rThis invention relates to couplers for connec ing vertically arranged rotary members. More particularly the invention relates to a coupler for connecting a vertical high speed driven shaft l with a non-aligning vertically suspended axis or shaft for an agitator, centrifugal separator or the like.

` High speed stirrers, agitators, centrifugals and the like are often supported on the lower end of a vertically mounted shaft or axis. If the driven axis is not in good alignment with the vertical driving shaft, a very great strain is placed on the bearings of the driving shaft. Furthermore, this non-alignment sets up severe bending strains in the shafts. In case the agitator. centrifugal or other part is directly suspended from the lower end of a vertical driving shaft undesirable strains may be placed on the bearings of the driving shaft if the product being treated by the agitator or the load in a centrifugal causes the parts to become unbalanced, especially when rotating at high speeds. A self-aligning coupling between vertically arranged driving and driven shafts will remove the bending strain on the shafts and the bearing strain.

The primary object of the present invention is to provide a coupler for vertically arranged shafts which is simple and efficient in operation.

A further object of the invention is to provide a coupler for vertically arranged shafts with a thrust bearing which has a very long life in operation. y Y

Another object of the invention is to provide a coupler for connecting the shaft of a driven member which is suspended from the lower end of a vertically aligned driving shaft.

With these and other objects in view the invention consists in the coupler for connecting vertically arranged shafts as hereinafter described, y

and particularly defined in the appended claims.

v'Ihe various features of the invention are illustrated in the accompanying drawings in which:

Figure .l is a view in vertical elevation with parts shown in section of a coupler embodying the preferred form of the invention for coupling a stirrer or agitator with a vertically arranged driving shaft; `vFigure 2 is a diagrammatic view illustrating the position of the connecting splines of the coupler when the vertically arranged shafts are in angular misalignment;

Figure 3 is a detail end View of the spline on the coupler block illustrating the shape of the alignment of the coupling member; and Figure 4 is a detail sectional view of a spline on the coupler block showing the .curved or arcuate form of the outer end of the splines.

Referring to Figure 1a coupler I0 is ut'lized for connecting a propeller drvenshaft I2 with a motor or gear driven shaft I4. The shaft I4 has a slight taper at its lower end which receives a bearingblocl I6. A keyway I6 is formed in the shaft I4 and block I6 to receive `a key 20 by which the block I6 vis fixed for rotation withl the shaft .,I4. The block is normally held in fixed position on the` tapered shaft by means of a nut 22 threaded on the lower end of the shaft I4.

As illustrated in Figure l, a propeller or agitator 24 ,which is fixed onthe lower end of the shaft I2 is suspended from the shaft I4 by the coupler Ill. In mostcases it is preferred to use a bottom bearing for the shaft I2 to hold it in fixed position, but the coupler I0 normally sustains uthe weight of the stirrerk or member attached to the bottom of the shaft I4.

To provide for the lthrust of the driven member upon the driving shaft the upper face of the block I6 has a spherical surface 26 which is arranged tocooperate with a similar spherical surface formed on thebottom of an inwardly projectingledge 28 on the inner surface of a cap 30 whichis attached to a cylinder 32 forming the outerportion of the coupler Il). The weightv of the shaft I2 with the stirrer 24 is supported by the spherical bearing surface 26. Y

VThe upper end of the shaft I2 has a slightly tapered surface whichv is fitted into a block or sleeve 34 forming the lower end of the coupler I0, A-keyway 36 is formed in the sleeve 34 Aand shaftl2 which is arranged to receive a key 38 by which the shaft I2 and coupler I0 will be fixed for rotationr with one another. The shaft is firmly held in position in the sleeve 34 by means of a nut 40, which is threaded uponthe upper end of the shaft I2. On the inner surface of substantially the bottom half of the cylinder 32 are formed a series of longisplines 42 which are arranged to receive splines 44formed on the bottom circumferential surface of the block I6. With this arrangement, the rotation of the shaft I4 to turn the block I6 willsimultaneouslyrotate thecylinder 32 and sleeve 34 to rotate the Shaft 12.

, An oil cavity 46 is formed in the top of the cap into which oil may be\inserted through an open:-

ing 48. A series of oil holes 50 are formed around the base of the cavity 46 by which oil may vflow from the cavity into the space between block I6 and thel cylinder 30 to lubricate the splines 42 and 44. The oil may pass around the inner edge of .i the cap 30 at the base of the cavity into the splines to permit a comparatively large angle of 4threaded through the plate and into a flange formed at the bottom of the cylinder 30. A drain opening 60 is formed at the edge of the oil plate by which oil from the inside of the coupler I may be removed: The? oil plate preventsv the escape of oil' into the bottom of theV ycoupler by which it might work out of the coupling along the keyway 3B. The cap 30 and the upper end1 of the cylinder 32 are fastened together: by; bolts 62, such bolts being uniformly distributed around the periphery of the cap. The angeat theflower end of the cylinder 32, the oilplateI andaange at the top of the sleeve 34 of the coupling are held together by means of distributed uniformly around the periphery of the cylinder.

In ordinary operationof the coupler, the oil cavityl 461- andi thespace betweenA the bloeliz- I6 andi cylinderV 32-i and the cavitybetweenA the oil plateand. the bottom of therblock I6 are'lled withV a lubricant which preferably: is aliquid. It is desirable-toprevent dirt from getting into the lubricant. Therefore* acover plate 66 having an inner-bore whichsnuglyy fitstheshaft isarranged to-havea-sliding mounting onaat surface 681at the top-of the coupling cap 3l);V Ifthe'tWo shafts assume a slightly angular position'in making ad'- justment for'nonfalignment, the capand cylinder ofY the coupler may move toward and from the shaftv I4, but thel plate 66 will close the space between the inner edgeofftheflat surface Eiland theshaft.

-In Figure 2 is: show-n in: a 'at layout position a diagram of. the splines 44 ofthe cylinder 32 and the splines 4-2fonthe block I6. Thediiferent positions ofA the'short-splines with reference to the longsplines. isr the position which theshort splines take in the coupler dueto Yan angular misalignment of the shafts; This diagraml shows that at one-side ofv a central posi-tion two-of the edges or corners ofthe short splinestend to bolts `lilLthe. bolts being;

4. In most cases, it is desirable to give an arcuate curvature to the ends of the splines, as well as to the faces of the short splines. Viewing Figure 3, it vwill be seen .that onlwa;smallclearancemust be provided between the side faces of the short splines and the side faces of the long splines so that this type of connection between the coupler vmembers will have a small amount of back lash.

The radial curvature of the side faces and ends or crownsv of the splines may be changed to permit differenty angular adjustments of the driving shafts; The curved-v faces on the short splines are very desirable. but: it is understood that the formation of such splines increases the cost of the coupling.

The preferred form of the invention having been` -thus described;` whatV is: claimedv as new is:

1. A coupling for vertically' arranged shafts comprisingrasupporting blockV to be fixedcn'the lower end of'a vertically arranged shaft, a hollow coupler arranged-e to enclose; and surround. the block, a spherical'I bearing surfaceV on the upper end of the block, a spherical thrust bearing surf-ace formed-within the couplerfand'contacting the spherical-v bearing surface onithe block, means-to holdlthecoupler inixed position on another veritically' aligned shaft, splines surrounding the lower Vperipheral' face--of the block and longer splines formed within: the'- coupler arranged to meshwith thesplines on the block, an oilchamber-'Yat the topof the coupler; and lubricantducts leading fromthe chamber to the spherical bearinga'ndithe splines.

2. YA coupling for) vertically arranged shafts comprising: a'supporting-bloek tobe-xed on the lower endof a verticallyarranged shaft, afhollow closely-f approachthe faces of the longY splines, v

while on the oppositeesideof the -central-position theother.v two edges ofthe shortsp-lines closely approach the faces of-'the lengsplines. In thev centralpositiony the short splines are centrally located' between the long splines. With this construction it wil-l be seen that the limit of the amounty cfangular adjustment whichwill-be permitted by thecoupler Hlis limitedto vthe amount of angular adjustmentfthat is permttedwhen the edges oftheshort splines strike thefaces off the lengv splines.

For most vertical shaft alignments the reetang'ular splines: will: provide a sufficientv angular adjustment off the shafts tof take carei of nonalignment and avoidstrain onAthe-shaftbearings. Withl some-types of machinery, such as stirrers; centrifugalsand thelike, which are'inclinedto get out of balancefdue--to the loading of" the mem-bersy orf the type'- of product being worked,- a greater angular adjustmentfof the shafts through the coupler is desired. To Lprovide for this, the short splines on theblock I6' are shapedrasshow-n in Figures-Bande.v It will be noted4 thati theside faces ofi'thef shorter splines have anarcuate curvature,- whichi willl permitA a greater angular relationship betweenA the shafts than :the rectangular typeofsplines illustratedin Figure- 2; Itwillbe-noted, furthermore, that the top edges or crowns of the short splines tend-Ito coupler arrangedV tov enclose andv surround the block; a sphericarbearing surfaceon'the upper end of the block, a-spherical thrust bearing surface form-edj within theL coupler and contacting the spherical bearing surface on the-block, means to holdtheecouplerfin fixe'dposition on another vertically alignedC shaft, splines surrounding the lower peripheral; face of the block and longer splinesl formed within the coupler arranged to mesh withthe splines on the'block, an oil chamvstrike the base of` theilong splineslas the anguber formedinl the'top of'- thecoupler, lubricant ducts leading from the chamber to the spherical bearing andl thesplines, and an oil plate below the fsplines toclose the coupler below the block' to hold oil-in the'coupling;

3. The coupling defined in claim 1 in which a' dust ring havingr a bore-to snugly ft the upper vertical shaftrisslidably'mounted' on a flat top surfaceof the coupling.

4;' The couplingdei-ined'in claim 1 inwhich-the hollow coupler is formed in twovparts with an oil plate-between thefparts in-the lower interior por'- tion of the coupler to form an oil chamber for submerging said splines irl-lubricant.

' HARRY C. MONROE.

REFERENCE-S CITED Thefol-lowing. references. are of record inthe 

